1 /*
2 * Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /*
25 * @test
26 * @bug 8260593
27 * @summary Verify that a temporary storage variable is or is not used as needed when pattern matching.
28 * @enablePreview
29 * @library /tools/lib /tools/javac/lib
30 * @modules
31 * jdk.compiler/com.sun.tools.javac.api
32 * jdk.compiler/com.sun.tools.javac.file
33 * jdk.compiler/com.sun.tools.javac.main
34 * jdk.compiler/com.sun.tools.javac.util
35 * @build toolbox.ToolBox toolbox.JavacTask
36 * @build combo.ComboTestHelper
37 * @compile LocalVariableReuse.java
38 * @run main LocalVariableReuse
39 */
40
41 import combo.ComboInstance;
42 import combo.ComboParameter;
43 import combo.ComboTask;
44 import combo.ComboTestHelper;
45 import java.io.IOException;
46 import javax.tools.JavaFileObject;
47 import toolbox.ToolBox;
48
49 public class LocalVariableReuse extends ComboInstance<LocalVariableReuse> {
50 protected ToolBox tb;
51
52 LocalVariableReuse() {
53 super();
54 tb = new ToolBox();
55 }
56
57 public static void main(String... args) throws Exception {
58 new ComboTestHelper<LocalVariableReuse>()
59 .withDimension("CODE", (x, code) -> x.code = code, Code.values())
60 .run(LocalVariableReuse::new);
61 }
62
63 private Code code;
64
65 private static final String MAIN_TEMPLATE =
66 """
67 public class Test {
68 #{CODE}
69 }
70 """;
71
72 @Override
73 protected void doWork() throws Throwable {
74 ComboTask task = newCompilationTask()
75 .withSourceFromTemplate(MAIN_TEMPLATE, pname -> switch (pname) {
76 case "CODE" -> code;
77 default -> throw new UnsupportedOperationException(pname);
78 });
79
80 task.withOption("-printsource");
81 task.generate(result -> {
82 for (JavaFileObject out : result.get()) {
83 try {
84 String actualDesugared = out.getCharContent(false).toString();
85 boolean hasTempVar = actualDesugared.contains("$temp");
86 if (hasTempVar != code.useTemporaryVariable) {
87 throw new AssertionError("Expected temporary variable: " + code.useTemporaryVariable +
88 ", but got: " + actualDesugared);
89 }
90 } catch (IOException ex) {
91 throw new AssertionError(ex);
92 }
93 }
94 });
95 }
96
97 public enum Code implements ComboParameter {
98 LOCAL_VARIABLE(
99 """
100 private boolean test() {
101 Object o = null;
102 return o instanceof String s && s.length() > 0;
103 }
104 """, false),
105 PARAMETER(
106 """
107 private boolean test(Object o) {
108 return o instanceof String s && s.length() > 0;
109 }
110 """, false),
111 LAMBDA_PARAMETER(
112 """
113 private void test(Object o) {
114 I i = o -> o instanceof String s && s.length() > 0;
115 interface I {
116 public boolean run(Object o);
117 }
118 """, false),
119 EXCEPTION(
120 """
121 private boolean test() {
122 try {
123 throw new Exception();
124 } catch (Exception o) {
125 return o instanceof RuntimeException re && re.getMessage() != null;
126 }
127 }
128 """, false),
129 RESOURCE(
130 """
131 private boolean test() throws Exception {
132 try (AutoCloseable r = null) {
133 return r instanceof java.io.InputStream in && in.read() != (-1);
134 } catch (Exception o) {
135 }
136 }
137 """, false),
138 FIELD("""
139 private Object o;
140 private boolean test() {
141 return o instanceof String s && s.length() > 0;
142 }
143 """,
144 true),
145 FINAL_FIELD("""
146 private final Object o;
147 private boolean test() {
148 return o instanceof String s && s.length() > 0;
149 }
150 """,
151 true),
152 ARRAY_ACCESS("""
153 private boolean test() {
154 Object[] o = null;
155 return o[0] instanceof String s && s.length() > 0;
156 }
157 """,
158 true),
159 METHOD_INVOCATION("""
160 private boolean test() {
161 return get() instanceof String s && s.length() > 0;
162 }
163 private Object get() {
164 return null;
165 }
166 """,
167 true),
168 ;
169 private final String body;
170 private final boolean useTemporaryVariable;
171
172 private Code(String body, boolean useTemporaryVariable) {
173 this.body = body;
174 this.useTemporaryVariable = useTemporaryVariable;
175 }
176
177 @Override
178 public String expand(String optParameter) {
179 return body;
180 }
181 }
182
183 }